Air-Assisted Fluid Stream Severance for Viscous Dispensing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional pumps face difficulties in dispensing high viscosity or viscoelastic flowable materials, such as toothpaste and honey, as they often result in elongated strings due to the viscosity and particulate matter, making complete severance of the fluid stream challenging.
Innovation Solution
The method involves injecting air into the fluid stream at the discharge outlet to assist in severing it, using a piston pump assembly with a two-piece piston construction that selectively collapses to discharge fluid and air, creating an air bubble that helps in breaking the fluid stream into distinct portions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If conventional pumps are used to dispense high viscosity flowable materials, then the dispensing mechanism is simple, but the fluid stream forms elongated strings that are difficult to sever
Solution Approach 1:
Air is introduced as an intermediary substance between the inner and outer portions of the fluid stream. The air bubble acts as a mediator that facilitates separation by creating a physical barrier and pressure differential, enabling clean severance of viscous fluid streams that otherwise would form continuous elongated strings
Solution Approach 2:
The fluid stream is divided into distinct segments by introducing air at a specific location within the discharge passageway. This creates separate inner and outer stream portions that are physically separated by the air bubble, preventing the formation of continuous elongated strings and enabling controlled dispensing
2Ease of operation
If air is injected into the fluid stream to assist severance, then the severance effectiveness is improved, but the device complexity increases
Solution Approach 1:
The two-piece piston construction serves multiple functions: it pumps the viscous fluid during the power stroke and simultaneously introduces air into the fluid stream during the return stroke. This multi-functionality achieves effective stream severance without requiring separate air injection equipment, thereby limiting the increase in device complexity
3Ease of operation
If the discharge passageway cross-sectional area is reduced to assist air flow, then the air injection effectiveness is improved, but the fluid flow resistance increases
Solution Approach 1:
The discharge passageway has varying cross-sectional characteristics: a larger cross-sectional area in the fluid delivery region to minimize flow resistance, and a reduced cross-sectional area at the air injection location to facilitate air bubble formation and stream severance. This local variation in geometry optimizes both fluid flow and air injection effectiveness
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach effectively breaks the fluid stream into separate portions, ensuring complete dispensing and preventing the formation of elongated strings, particularly effective for viscous and viscoelastic materials by utilizing the sudden collapse of the air bubble to generate sufficient pressure for severance.
Implementation Method 1
The extent to which the viscous or viscoelastic fluid will have an impact on whether an air bubble may be formed in the discharge passageway by the injection of air. The creation of an air bubble and its subsequent sudden violent discharge can be of substantial assistance in providing for a complete severance of viscous and viscoelastic fluids.
Implementation Method 2
utilizing the sudden collapse of the air bubble to generate sufficient pressure for severance
Implementation Method 3
The present invention provides a piston pump assembly with a two-piece piston construction that selectively collapses to discharge fluid and air
Data Source
AI summary
Methods and apparatus for dispensing flowable fluids, particularly those which are high viscosity by passing a stream of fluid through an elongate discharge passageway and injecting air into the fluid stream to initiate severing of the stream between an inner portion inward of the injected air and an outer portion outward of the injected air.